Archery bow



W. L. MILLER ARCHERY BOW April 20, 1943.

Filed 001'.. 28, 1941 .nml v Patented Apr. zo, 1943 I UNITED STATES'PATENT OFFICE' ABCHERY BOW Walter L. Miller, Teaneck, N. J.

Application October 28, 1941, Serial No. 416,810

2 Claims.

The present invention relates generally to improvements in archery bows,and it has relation specifically to a reinforced wooden archery bow andthe method of constructing the same.

Archery bows are made generally of solid pieces of various woods, orlaminated plies of such woods, having comparatively good elasticqualities. Such bows, however, have one common fault of being muchweaker in compressive strength than in tensile strength. When a woodenbow is deflected for casting purposes, the wood on the belly, which isthe concave side of the bow next to the archer, is compressed while thewood on the back, which is the convex side of the bow away from thearcher, is placed under great tensile strain. Repeated or continualdeflection of a bow causes the Wood to take a permanent set in thedirection of its bend or deflection, which set is due principally to theinherent weakness of the wood in compression.

This set causes a great loss in eiciency or cast in the bow.Consequently, rare pieces of wood y that take comparatively little setin use are valued highly by archers.

Numerous attempts have been made to overcome this setting tendency inwooden bows by applying materials, such as rawhide, vulcanized ber,silk, linen or bamboo to the back of bows. Such a construction,however', does not correct the compressive weakness in such bows, andonly visually appears to correct the set by pulling the bow backwardlyor -in a direction reverse to that I of its normal cast deflection. Bowsof such constructions do not have the proper tone resilience until afterthey are deflected normally to a position equal to the amount of theiroriginal set. This lack of resilience in compression causes a shiftingof the neutral plane during flexing of the bow with the unsatisfactoryresult that such bows have'insulcient sti'ness at the beginning of theirdraw as compared with their stiffness at the end of their draw.

Bows have also been made with a re-curved or backwardly curved limbportion in an attempt to -counteract this normal tendency to set. Such aconstruction results in a greater deection of the bow limbs during thedraw, and such bows are, therefore, much more likely to break when beingused in casting.

The compressive weakness of all bow woods is increased or aggravated byincreased humidity or increased heat. Such compressive weakness asresults from changes in temperature causes a considerable drop in theefficiency or casting power and other desirable qualities of a bow,

making casting with such bows extremely unsatisfactory in warm and humidweather.

An object of the present invention is the pro- I vision of a simple,eicient and inexpensive construction for archery bows which is capableof correcting the compressive weakness of the wood in an archery bow,thereby greatly increasing the useful life and casting power thereof.

Another object of the invention is to provide a construction for awooden archery bow which will make it resistant to heat and moisture tosuch a high degree that atmospheric changes will have substantiallylittle or no effect on the casting power thereof.

A further object of the invention is the provision of a new, simple andelcient method of constructing an archery bow embodying the principlesof the invention.

Other and further objects and advantages of' the invention reside in thedetailed construction of the bow, which result is simplicity, economyand eiciency, and which will be apparent from the following description,wherein preferred forms of embodiment of the invention are shown,reference being had to the accompanying drawing, forming a part hereof,whereinlike numerals indicate like parts, in which:

Fig. 1 is a fragmentary vertical sectional view of an archery bow madein accordance withthe invention, illustrating the steps in the method ofsecuring the several parts together while being deflected backwardly orin a reverse position;

Fig. 2 is a fragmentary vertical sectional View of the archery bow shownin Fig. 1, with the clamping elements removed, and showing its positionwhen it is not under deflection;

Fig. 3 is a fragmentary vertical sectional view of. the archery bowshown in Fig. 2, showing the bow string attached, the'bow being bracedand ready for casting;

Fig. 4. is a cross-sectional view of the bow shown in Fig, 2, the samebeing taken along the line 4 4 thereof, looking in the direction of thearrows;

Fig. 5 is a cross-sectional view of the bow shown in Fig. 2, the samebeing taken along the line 5-5 thereof, looking in the direction of thearrows;

Fig. 6 is a cross-sectional view, on an enlarged scale, of one form ofplastic strip material which may be used for facing the belly of thebow;A

Fig. 7 is a cross-sectional view, on an enlarged scale, of another formof plastic strip .material of a laminated construction, which may beused for facing the belly of the bow;

Fig. 8 is a cross-sectional view. on an enlarged scale, of still anotherform of plastic strip material of a laminated construction, which may beused for facing the belly of the bow;

Fig. 9- is a cross-sectional view, on an enlarged scale, o! stillanother modied formv of plastic stripmaterial having shredded fibrousmaterial incorporated therein', which may be used for facing the bellyof the bow; and

Fig. 10 is a fragmentary cross-sectional view of the handle section of amodified form of archery bow mad'e in accordance with the invention,showing the facing material applied in the form of separate continuousstrips covering each limb of the bow.

Referring now to the drawing, there is shown in Fig. 1 a wooden basemember I2 deected backwardly in a manner reverse to its normal castingposition. The base member I2 may be deected and held in such reversedeflected position in any suitable or convenient manner (ndt shown). In

this deflected position the back I4 of the bow I2 is put under acompressive strain and its belly I6, which has been previously properlyfinished or prepared for receiving a facing strip material, is

placed under a substantial tensile strain. While the bow I2 ismaintained in such a reverse deiiected position, there is appliedadhesively there.. to a relatively thin strip of a thermo-settingresinous material I8 to the Ibelly or tension side thereof. I'he stripI8 may vary somewhat in thickness depending upon the kind of wood usedin making the base member I2 and its thickness dimensions. l

I have found, however, that when the facing strip I8 is less than onethirty-second of an inch in thickness, its compressive and reinforcingstrength is insufficient to improve the casting power of the bow. andthat when the facing strip I8 is more than one quarter of an inch inthickness, its mass is such that its efilciency cannot be utilized. Theplastic thermo-setting resins that I have found suitable for use as asatisfactory fac` ing strip for the belly of archery bows may be Adesignated generically as a thermo-setting resin,

such as for example, phenol formaldehydes, urea formaldehydes or otherthermo-setting aldehyde compounds combined with any suitable combiningcomponent. Each of the resins of these groups have a compressivestrength of at least two to four times that of the wood used in formingthe base member, which is essential for improving the casting power ofthe bow. A plastic substance having a compressive strength less thantwice that of the wood in the wooden base member would not havesufficient advantages to warrant its use in a bow. Furthermore, each ofthe thermo-setting resinous plastics herein enumerated are resilient,waterproof and substantially unaected by heat and humidity, which meansthat they will not be noticeably affected by changes in climaticconditions. Therefore, when incorporated in an archery bow in the mannerdescribed, the bow will give substantially constant casting powerregardless of the prevailing temperature or humidityL which is highlydesirable since most archery contests are held out of doors where thebows would be subjected to prevailing atmospheric conditions. The handleportion 22 may now be adhesively treated and positioned over the stripI8, if desired, and the entire assembly clamped and held tightlytogether by any conventional means, such as for `example, by a suitableflexible clamping strip 24, Y which is removably secured at spacedintervals `by means of conventional wood clamps 26. The strip 24 andseries of spaced lamps 26 serve to hold the plastic strip I8 in placeagainst the base member I2 until the adhesive material 20 has becomethoroughly dried, after which they may be removed and the assembled bowfinished and varnished in the ordinary manner. The back portion 28 ofthehandle member maybe amxed at any convenient time.

When the clamping strip 24 and its clamps 28 are removed, and theassembly is released from its backwardly deflecting'means, it will tendto straighten out, but due to the high compressive strength of theplastic material of the facing strip I8, which has been applied under acompressive strain, a slight reverse deflection will/remain in the bowI2,asbest showninFlg. 2.

In Fig. 3 the bow string 88 has been strung on the bow I2, and theassembly assumes its normal braced position. It is obvious that, whenthe bow assembly is placed under a normal deflection. the plastic facingstrip material I8 will be placed under a considerable increasedcompressive strain, which will be further increased at full draw.

The relatively thin strip I8 of plastic may, if desired, have variousconstructions without departing from the spirit of my invention. In Fig.6 the facing strip I8 is shown made solidly of a thermo-setting plasticresinous material 82.- It

. layers of plastic 36 and fabric, paper or other fibrous material 38.These layers of fabric,

paper, etc. serve to reinforce the thme-setting' resinous plasticmaterial 36, thereby tending to prevent fracturing, breaking, etc. Inthis construction, the attaching side of the strip 84 is provided withan exposed facing 39 of the reinforcing material 38 which serves tofacilitate its attachment to the wooden base of the bow.

In the modication shown in Fig. 8, the plastic facing strip 48 isprovided merely with a fabric, vulcanized fiber orother binding strip42, which may be preferably molded thereto. The lstrip 42 may, however,be separate, if desired, and used merely for mounting the strip 40 uponthe belly I6 of the bow I2. In the event the binding strip 42 is formedseparate from the plastic strip 40, it may be first mounted on thewooden bow and then the strip 40 may be adhesively secured thereto, orvice versa.

In Fig. 9 the plastic strip 44 is shown reinforced with a shreddedfibrous material 46, such as for example, shredded paper, cotton, wool,fabric or other suitable reinforcing'materials. Portions of the fibersof the material 46 will become exposed when sanded preparatory toapplying to the bow, and these exposed portions greatly facilitatesecuring the same to said bow.

In Fig` 10 there is shown a modified form of bow construction 5B,wherein the strip of plastic material does not pass continuously throughthe same is free of strain during casting and no casting advantage isgained thereby.

It is apparent from the above description of the invention that theultimate desire is the application to the belly of 'a wooden archery bowof a facing strip of a thermo-setting resinous plastic material undera'high degree of compression. While rthere is illustrated in the drawingonly one simple method of accomplishing this result, it will be readilyunderstood that other methods may be employed without departing from thespirit of the invention. For example, another method that may beadvantageously employed by archers would be to cut the plastic facingstrip material to a length slightly longer than the length of the bow towhich it is intended to be applied. Then securely fasten the ends ofsuch facing strip material to the ends of the bow, which will cause theintermediate portion of the plastic strip material to form a bulgeoutwardly and away from the corresponding portion of the belly of thebow. Such a bulge may be removed by gradually applying sufficientexternal pressure to that portion of the facing strip material to causeit to be compressed until it will lay flat along the surface of thebelly of the bow. This intermediate portion which has been adhesivelytreated may then ybe secured to the belly of the bow and heldthereagainst by external pressure until the adhesive has becomethoroughly dry. By factory methods it may be possible to precompress theplastic facing strip material, and then apply it to the belly of the bowin such precompressed condition to attain the desired result in thefinished bow.

With the present invention it is possible to construct archery bowshaving good casting power out of inferior and cheaper woods.Furthermore, archery bows embodying the invention have greatlyincreasedcasting power over archery bows constructed solely of woodidentical to the wood used in making the base member of my improved bow.Bows made according to the present invention are substantiallyunaffected by heat and moisture, and, as `a result, have substantiallyconstant casting' power regardless of prevailing atmospheric conditions.With the present invention the normal and useful life of wooden archerybows is greatly increased, and the likelihood of breakage due tocompressive collapse during casting is greatly diminished.

' The present invention may readily be applied to existing bows, and isnot limited in its application to the construction of new archery bows.In the event an archer is desirous of applying a plastic facing strip I8to his old bow, this may conveniently be done merely by removing fromthe limb an amount of wood approximately equal to the thickness of theplastic strip to be applied. The plastic strip I8 may then be applied inthe identical manner described hereinabove in connection with thebuilding of a new bow. After the facing strip I8 is applied to thewooden base member I2, the assembly maybe finished and varnished as inthe case of a new bow.

When use is made of the 'expression thermosetting plastic material inthe claims, I mean to include such material in any of the various formsillustrated in the drawing, viz: solid plastic material, laminatedplastic material or plastic material reinforced with shreddedreinforcing matter.

Although I have only described in detail sev--` eral modifications whichthe invention may assume, it will be readily apparent `to those skilledin the art that the same is not to be so limited, but that various othermodifications may be made therein without departing from the spiritthereof or from the scope of the appended claims.

What I claim is:

l. An archery bow comprising a wooden base member having its belly facedwith a relatively thin strip of a thermo-setting plastic material thathas been applied so as to be under a compressive strain when said bow isunbraced and at rest, said thermo-setting plastic material conf sistingof an aldehyde compound combined with any suitable combining component.

2. An archery bow comprising a wooden base member having a pair ofoutwardly and oppositely extending limb portions, each of said limbportions being covered with a relatively thin flexible strip ofthermo-setting plastic material that has been applied in such a mannerthat said material is under a compressive strain when said bow isunbraced and at rest, said thermo-setting plastic material consisting ofan aldehyde compound combined with any suitable combining component.

WALTER L. MILIER.

